The present invention relates to electro-optic (EO) seekers and, more specifically, to EO seekers with ultrasonic piezo-electric motors for driving a sensor ball.
Missile guidance refers to a variety of methods of guiding a missile or a guided bomb to its intended target. The missile's target accuracy is a critical factor for its effectiveness and guidance systems improve missile accuracy by improving its “Single Shot Kill Probability” (SSKP). Guidance technologies can generally be divided into a number of categories, with the broadest categories being “active,” “passive” and “preset” guidance. Active guidance refers to cases in which guidance signals are generated in real time on board a missile. Passive guidance refers to cases in which guidance signal home in on a signal generated by the target. Preset guidance refers to cases in which guidance signals are preset and loaded into a missile prior to launch.
For active and passive guidance, traditional missile seekers typically include a sensor and often require a gimbaled system be coupled to that sensor. The gimbaled system enables a field-of-view (FOV) of the sensor to permit the senor to scan over time a full field-of-regard (FOR). The size, weight and power and cost (SW&P/C) for such gimbaled system hardware is always a considerable challenge, however, when faced with high performance and low cost requirements normally associated with missile design.
Thus, gimbaled system hardware for missile seekers has been developed with an eye toward size and weight reductions for small diameter airframes. This has led to a ball joint gimbal (BJG) design in which a dual sensor is housed on a sensor ball and is controlled by Kevlar™ tendons that are motor driven from within a seekerhead housing. These motors tend to consume a considerable amount of space within the seeker-head housing, however, and are relatively expensive.